(CNN) -- Hurricane Danielle, a Category 4 storm, will bring large waves to Bermuda and will likely cause rip currents along the East Coast of the United States, the National Hurricane Center said on Friday.
Maximum sustained winds were near 135 mph, with higher gusts, it said. A tropical storm watch was issued for Bermuda.
Even though the center of the storm is expected to pass well to the east of Bermuda on Saturday night, "large waves and dangerous surf conditions will affect Bermuda over the next few days," the center said.
It also indicated swells from Danielle will arrive on the East Coast of the United States on Saturday, and will likely cause dangerous rip currents through the weekend.
"A turn toward the north-northwest is expected by tonight followed by a turn toward the north on Saturday," the latest hurricane advisory said.
Friday evening, Danielle was about 410 miles southeast of Bermuda.
Traveling behind Danielle, also far from land, Tropical Storm Earl's winds swirled near 45 mph Friday evening, with higher gusts. The hurricane center forecast that Earl, which was moving toward the west, could become a hurricane by Sunday.
If so, Earl would be the third hurricane of the 2010 Atlantic season, following Danielle and Hurricane Alex.
Earl is expected to strengthen and will be closer to the United States and probably create larger waves, said CNN meteorologist Chad Myers.
Although it is not currently predicted to strike the United States, a move that way can't be ruled out over the next seven days, Myers said.
A tropical storm watch was in effect for the French islands of St. Martin and St. Barthelemy in the Caribbean.
Residents in the northern Leeward Islands, about 1,080 miles west of Earl, were urged to monitor Earl's progress.
Earl is expected to follow a path similar to Danielle's, although likely farther south and west, which could mean more of an impact on Bermuda.
A third weather system also is being watched. A low-pressure system 175 miles south of the Cape Verde Islands could become a tropical depression during the next couple of days, the Hurricane Center said. It added there is an 80 percent chance of this system becoming a tropical cyclone during the next 48 hours.
Alex was a Category 2 system that caused widespread damage and some deaths in northern Mexico after it made landfall on June 30 near the border between Mexico and Texas, according to the Mexican government news agency.